A tube connector of a generally useful type is exemplified in Pleickhardt et al. U.S. Pat. No. 4,518,293, which discloses several forms of such a connector. In certain forms, the tube connector is adapted to receive a threaded fastener In another form, the tube connector includes, as one of its components, a threaded fastener In each form, except for the threaded fastener, the tube connector is made from a sheet metal stamping.
Tube connectors of more specialized types are exemplified in Tinnermann U.S. Pat. No. 2,618,009 and Swick U.S. Pat. No. 3,006,673. Such connectors are useful to connect fittings to tubular legs for furniture.
Typically, as exemplified in each of the three patents noted above, a tube connector employs sharp-edged, radially extending legs, which flex axially so as to facilitate insertion of the tube connector into a tube, but which dig aggressively into the tube wall so as to resist withdrawal of the tube connector from the tube, and so as to resist rotation of the tube connector within the tube.
One disadvantage of a tube connector, as exemplified in Pleickhardt et al. U.S. Pat. No. 4,518,293, is that a lateral force, if imparted to a threaded fastener received by or included in the tube connector, tends to distort adjacent sheet metal portions of the tube connector and to cause the threaded fastener to cant out of axial alignment with the tube. The disadvantage is not overcome in tube connectors exemplified in the other patents noted above.